Effect of fluorinated silicate glass passivation layer on electrical characteristics and dielectric reliabilities for the HfO2/SiON gate stacked nMOSFET

Abstract

The superior characteristics of the fluorinated hafnium oxide/oxynitride (HfO2/SiON) gate dielectric are investigated comprehensively. Fluorine is incorporated into the gate dielectric through fluorinated silicate glass (FSG) passivation layer to form fluorinated HfO2/SiON dielectric. Fluorine incorporation has been proven to eliminate both bulk and interface trap densities due to Hf-F and Si-F bonds formation, which can strongly reduce trap generation as well as trap-assisted tunneling during subsequently constant voltage stress, and results in improved electrical characteristics and dielectric reliabilities. The results clearly indicate that the fluorinated HfO2/SiON gate dielectric using FSG passivation layer becomes a feasible technology for future ultrathin gate dielectrics applications. (C) 2010 Elsevier B.V. All rights reserved.